Marine propulsion unit



Aug. 20, 1968 5. THEN ET AL 3,3

MARINE PROPULS I ON UN IT Filed Nov. 16, 1966 5 Sheets-Sheet 1 INVENTORS. SOPHIA THEN ALOJZY THEN 5&

AT TOPNE YS Aug. 20, 1968 5 THEN ET AL MARINE PROPULS ION UNIT 3 Sheets-Sheet 2 Filed Nov. 16, 1966 l/llllll/Ill/ll/l/llll/l/lI/Illrllll/l/Il/ m am INVENTOR5. SOPHIA THEN ALOJZY THEN ATTORNEYS Aug. 20, 1968 5. THEN ET AL MARINE PROPULSION UNIT 5 Sheets-Sheet 5 Filed Nov. 16, 1966 INVENTORS. SOPHIA THEN ALOJZY THEN AT TOPNE YS United States Patent 3,397,538 MARINE PROPULSION UNIT Sophia Then and Alojzy Then, both of 1637 Connie Ave., Madison Heights, Mich. 48071 Filed Nov. 16, 1966, Ser. No. 594,797 7 Claims. (Cl. 60221) ABSTRACT OF THE DISCLOSURE A marine propulsion unit for propelling a boat and which comprises a support housing for mounting the propulsion unit on a boat, a propeller housing rotatably mounted on said support housing and provided with fluid intake means and fluid outlet means, a pair of counterrotatable propellers mounted in said propeller housing for drawing fluid into the housing through said intake means and discharging the fluid through said outlet means in a jet stream to provide a propelling resultant forward thrust on the boat, means operatively mounted in the support housing for connecting the propellers to a power means in the boat, and, means connected to said propeller housing for rotating the propeller housing from a normal position with the outlet means facing away from the boat to propel the boat forwardly to a position to dispose the outlet means toward the forward end of the boat for reversing the direction of movement of the boat.

This invention relates generally to improvements in marine propulsion means for boats, and more particularly to a novel and improved marine propulsion means which is adapted to provide an outboard propulsion unit powered by an inboard motor.

It is an important object of the present invention to provide a novel and improved marine propulsion unit which is adapted for use in shallow water and which embodies a pair of counterrotatable propellers that create a pair of converging water-jets that provide a propelling forward thrust on a boat without turning the boat.

It is another object of the present invention to provide a novel and improved marine outboard propulsion unit which is adapted to 'be driven by an inboard power means, and which is simple and compact in construction, economical to manufacture, easy to steer and maneuver, and efficient in operation.

It is still another object of the present invention to provide a novel and improved marine propulsion unit which incorporates a propeller housing having an upper compartment and a lower compartment, a propeller rotatable on a substantially horizontal plane in each compartment, an inlet opening on the top end of the upper compartment and an inlet opening on the bottom end of the lower compartment, a first outlet opening in the rear wall of the upper compartment and a second outlet opening in the rear wall of the lower compartment, and, said outlet openings are offset vertically and horizontally from each other.

It is still a further object of the present invention to provide a novel and improved marine propulsion unit which includes a pair of counterrotatable propellers disposed for rotation on substantially horizontal planes, vertically spaced apart from each other, and driven by a pair of substantially vertical, telescopically disposed drive shafts.

It is still another object of the present invention to provide a marine propulsion unit for propelling a boat which comprises a support housing for mounting the propulsion unit on a boat, a propeller housing rotatably mounted on said support housing and provided with fluid intake means and fluid outlet means, a pair of counter- "ice rotatable propellers mounted in said propeller housing for drawing fluid into the housing through said intake means and discharging the fluid through said outlet means in a jet stream to provide a propelling resultant forward thrust on the boat, means operatively mounted in the support housing for connecting the propellers to a power means in the boat, and, means connected to said propeller housing for rotating the propeller housing from a normal position with the outlet means facing away from the boat to propel the boat forwardly to a position to dispose the outlet means toward the forward end of the boat for reversing the direction of movement of the boat.

Other objects, features and advantages of this invention will be apparent from the following detailed description, appended claims, and the accompanying drawings.

In the drawings:

FIG. 1 is a rear elevational view of an outboard marine propulsion unit made in accordance with the principles of the invention;

FIG. 2 is a slightly reduced, elevational section view of the structure illustrated in FIG. 1, taken along the line 22 thereof, and looking in the direction of the arrows} and FIG. 3 is a horizontal section view of the structure illustrated in FIG. 1, taken along the line 33 thereof, and looking in the direction of the arrows.

Referring now to the drawings, and in particular to FIG. 2, the numeral 10 generally indicates a power driven shaft for driving the marine propulsion unit of the present invention. The shaft 10 may be powered by any suitable means, as for example, by a two-cycle, air cooled internal combustion engine of the type used in conventional outboard motors, or it may be powered or driven by any conventional inboard type engine. As shown in FIG. 2, the shaft 10 is shown as extended through a bore 11 in a suitable support plate 12 adjacent an inboard engine generally indicated by the numeral 13.

As shown in FIG. 2, the drive engine 13 is illustrated as being supported by a plate 14 which in turn is supported by a bracket means in the boat 20. The boat 20 is shown in fragmentary, broken configuration and as having an aft and stern wall 19. The engine supporting bracket means includes a bracket leg 15 on one side of the boat which has the rear end thereof hinged at the point 17 to a further bracket or strap 18. The strap 18 is secured to the boat rear end wall 19 by any suitable means, as by the screw 21 and the wing nut 22. The inner end of the bracket 15 is integralwith the vertical bracket 23 which in turn is integral with the horizontal bracket portion 24. The bracket portion 24 is secured to the bottom wall 28 of the boat 20 by any suitable means as by the spacer 25, the screw 26 and the bolt 27. As shown in FIG. 1, the left or port side of the boat 20 is provided with a similar boat supporting means as shown by the rear end of the screw 21a and wing nut 22a. The above supporting means shown in FIG. 2 would be disposed on the right or starboard side of the boat 20.

As shown in FIG. 2, the propulsion unit of the present invention includes a support housing having a vertically disposed tubular portion 29 which is open on the upper end thereof and on the lower end thereof. The upper end of the support housing portion 29 is enclosed by a cover or cap 30 that is threadably mounted in the upper open end of the tubular support housing portion 29. The support housing portion 29 is provided with a circular threaded opening 31 on the front end thereof which faces the boat 20. The support housing includes a second tubular portion 3-2 which has its inner end threadably mounted in the opening 31 in the support housing portion 29 and the outer provided with a circular flange 33. As shown in FIG. 2, the flange 33 is provided with a gasket 34 and is detachably secured to the support plate 12 by any suitable means, as by a plurality of screws 35.

As shown in FIG. 2, the support housing further includes a third portion 36 which is slidably mounted within the lower open end of the support housing portion 29 and secured in a desired adjusted position by any suitable means, as by a plurality of set screws 37. The support housing further includes a fourth portion 38 which is formed in the shape of a cylinder with an upper end which is open and a lower end which is open and with the upper end threadably mounted in the lower end of the housing portion 36.

As shown in FIG. 2, the power driven shaft extends into the support housing portion 32 and carries on its outer end a suitable clutch drive member 39 which is operatively engageable with a driven clutch member on the outer end of a tubular shaft 40. The shaft 40 is secured by any suitable means, as by being splined thereto, onto the drive gear indicated by the numeral 41. As shown in FIG. 2, the clutch drive member 39 is provided with suitable driving dogs 42 which are engageable in mating recesses 43 formed on the outer end of the shaft 40. When the clutch drive member 39 is moved to the left, as viewed in FIG. 2, to the broken line position indicated by the numeral 44, the drive shaft 10 is disengaged from the drive gear 41.

As shown in FIG. 2, the gear 41 is a bevel gear and it drives a first driven bevel gear 45 which is mounted on the upper end of a propeller drive shaft 46, and secured thereto by means of a screw 47. The bevel gear 41 also drives a second driven gear 48 which is spaced downwardly from the first driven gear 45 and which is secured to a tubular propeller drive shaft 49 by a. screw 59.

As shown in FIG. 2, the upper end of the propeller drive shaft 46 is rotatably mounted in the support housing cover 30 by any suitable means, as by the thrust of bearing 51. The second driven gear 48 is supported by the thrust bearing 52 which is in turn supported by the angular spacer member 53 that is mounted on the inside of the support housing tubular portion 36. It will be seen that the gear 41 drives the driven gear 45 in one direction and the driven gear 48 in the other direction to provide a pair of counter-rotating shafts 46 and 49. The shafts 46 and 49 are provided with a sleeve bearing 54 between each other at the upper ends of the shafts and a similar sleeve bearing 55 at the lower end of the shafts. The lower end of the shaft 49 is rotatably supported in the lower end of the support housing portion 38 by any suitable means, as by the needle bearing means 56.

As shown in FIG. 2, the propulsion unit of the present invention includes a first or upper propeller generally indicated by the numeral 57 which is secured to the lower end of the tubular shaft 49. As shown in FIGS. 2 and 3, the propeller 57 comprises an elongated horizontal plate 58 which is integral with a centrally mounted hub 59 that has a bore therethrough to receive the tubular shaft 49. The propeller hub 59' is secured to the shaft 49 by any suitable means, as by a lock screw 60. The propeller 57 is provided with a pair of fixed, vertically disposed blades 61 and 62 which are disposed on the centerline of the plate 58. As shown in FIG. 3, the ends of the plate 58 are formed pointed or in triangular shape.

As shown in FIG. 2, the propulsion unit of the present invention includes a second or lower propeller, generally indicated by the numeral 63, which is disposed in a spaced apart position downwardly from the upper propeller 57. The propellers 57 and 63 are similar in construction and identical in length and fluid actuating capacity. The lower propeller 63 includes the elongated plate 64 which is provided with a central hub 65 that is secured to the lower end of the drive shaft 46 by any suitable means, as by the p n 66 and the snap or lock ring 67. The propeller 63 further includes the vertically disposed blades 68 and 69 on the lower side thereof.

It will be seen that the drive shaft 46 is telescopically mounted in the drive shaft 49 and that these shafts are substantially vertically disposed in operation.

As shown in FIGS. 1, 2 and 3, the propulsion unit of the present invention further includes a propeller housing, generally indicated by the numeral 70. The propeller housing is substantially cylindrical in overall configuration and is provided with a cylindrical side wall 71, an integral horizontal top end wall 72 and an integral horizontal bottom end wall 73. The propeller housing 70 further includes an intermediate horizontal dividing wall 75 which divides the :propeller housing into an upper propeller compartment 76 and a lower propeller compartment 77. As shown in FIG. 2, the propeller drive shaft 46 extends downwardly through an axial hole 78 formed through the propeller housing wall 75 and the shaft 46 is provided with a seal member 79 at the point where it extends through the opening 78. The upper propeller 57 is thus rotatably supported in the upper compartment 76 and the lower propeller 63 is rotatably mounted in the lower compartment 77.

The propeller housing 70 is provided with a suitable intake means for drawing fluid, into the housing. The fluid intake means comprises a circular opening 80 which is formed through the housing top end wall 72 and an intake opening 81 which is formed through the housing bottom end wall 73.

As shown in FIG. 1, the propeller housing 70 is provided with an outlet means on the rear end of the housing. The fluid outlet means comprises the pair of outlet openings 82 and 83 formed through the rear end walls of the upper and lower compartments 76 and 77, respectively. As seen in FIG. 1, the outlet openings 82 and 83 are horizontally and vertically ofiset from each other and they are on opposite sides of the centerline or axis of the housing 70. It will be seen that fiuid being discharged from the openings 82 and 83 will be directed toward the centerline of the housing or they will converge due to the circular construction of the propeller housing 70. As shown in FIG. 3, the outlet opening 83 extends for an arcuate distance around the periphery of the inner housing between the points indicated by the numerals 84 and 85. The outlet opening 83- extends for a similar arcuate distance as indicated by the end points 86 and 87. The outlet openings 82 and 83 have a height equal to the dis tance between the end walls and the intermediate or dividing wall 75.

The propeller housing 70 is rotatably supported on the marine {propulsion unit support housing by the following described structure. As shown in FIG. 1, the propeller housing 70 is provided with three upwardly extended elongated screws 88 which have the lower ends threaded in the housing 71} and secured thereto by the lock nuts 89. As shown in FIGS. 1 and 2, the upper ends of the screws 88 are secured to a carrier plate 90 by means of the lock nuts 91 and 92. The carrier plate 91 is preferably circular in plane view and is provided with a central or axial flange 93 in which is received the lower end of a tubular shaft 94 to which it is secured by any suitable means, as by welding. The tubular shaft 94 is rotatably mounted about the lower portion 38 of the support housing and is secured thereto by the locking sleeve 95 which is threadably mounted on the lower end of the housing portion 38. A suitable O-ring seal 96 is mounted within the lower end of the housing portion 38 and secured in place by a releasable snap ring 97 carried on the inside of a flange on the lower end of the locking sleeve 95.

As shown in FIG. 2, a steering means or means for rotating the propeller housing is operatively connected to the upper end of the tubular shaft 94. The last mentioned means is generally indicated by the numeral 98 in FIGS. 1 and 2, and it includes a pulley having a hub surrounding the shaft 94 and secured to a pair of outwardly extended projections or ears 99, as shown in FIG. 2, by means of a pair of lock screws 100. A steering cable 101 is operatively mounted around the pulley portion 102 of the steering means, and the cables are adapted to be extended into the boat for rotating the propeller housing 70 to turn the housing for steering the boat 20. The propeller housing 70 is disposed in a normal position, as shown in FIG. 1, when the boat is moving forwardly. When it is desired to propel the boat backwardly, the steering cable 101 is operated so as to rotate the tubular shaft 94 and the propeller housing 70 in a circular direction approximately 180 so as to dispose the outlet openings 82 and 83 in a direction facing the boat 20 to provide a rearwardly directed thrust on the boat. It will 'be understood that the propeller housing 70 may be adjusted upwardly and downwardly by means of the supporting screws 88 so that the bottom end of the propeller housing 70 may be disposed relative to the bottom wall 28 of the boat 20 in any desired position. The length of the drive shafts 46 and 49 would be made in accordance to the desired position of the propeller housing 70 relative to the bottomof the boat 20.

It will be seen that, in operation, the propellers 57 and 63 will be driven in opposite directions in accordance with the direction of rotation of the power drive shaft 10. The counter-rotating propellers will draw fluid, that is, water, through the inlet openings 80 and 81 and propel the same outwardly in a water-jet through the outlet openings 82 and 83' to provide a propelling resultant power thrust on the boat when the propeller housing is disposed in the position :shown in FIG. 1. Experience has shown that the propulsion unit of the present invention is particularly adaptedto propel a boat in shallow water so as to avoid obstacles. The counterrotating propellers 57 and 63 provide a pair of converging water-jets which eliminate any turning effect to one side or the other on the boat. The propulsion unit of the present invention is efficient and easy to use and may be steered with a minimum of effort. I

The propulsion unit of the present invention provides a drive means wherein the load inside of the boat can be more evenly distributed since the drive motor is inside of the boat and can be disposed in any desired position. The propulsion unit can be used with motors of different power by merely changing the propellers so as to provide a propeller corresponding to the power to be impressed on the propellers. The propulsion unit is easily transported and can be quickly and easily disassembled and assembled for repair or mounting purposes. The propulsion unit of the present invention is safe in operation and may be quickly and easily fabricated from a minimum of easily machined parts. In one embodiment a fourteen foot boat was efficiently propelled by a propulsion unit made in accordance with the invention which has a seven inch blade and was driven by a four horse power engine.

While it will be apparent that the preferred embodiment of the invention herein disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A marine propulsion unit for propelling a boat comprising:

(a) a support housin for mounting the propulsion unit on a boat;

(b) a propeller housing rotatably mounted on said support housing and provided with fluid intake means and fluid outlet means;

(0) a pair of counterrotatable propellers mounted in said propeller housing for drawing fluid into the housing through said intake means and discharging the fluid through said outlet means in a jet stream to provide a propelling resultant forward thrust on the boat;

(d) means operatively mounted in the support housing for connecting the propellers to a power means in the boat;

(e) means connected to said propeller housing for rotating the propeller housing from a normal position with the outlet means facing away from the boat to propel the boat forwardly to a position to dispose the outlet means toward the forward end of the boat for reversing the direction of movement of the boat;

(f) each of said propellers being mounted for rotation on a substantially horizontal plane;

(g) said intake means comprising an intake opening on the top end of said propeller housing and an intake opening on the bottom end of said propeller housing;

(h) said propeller housing being divided by a wall into an upper compartment and a lower compartment, with one of said propellers being rotatably mounted in the upper compartment and the other of said pair of propellers being mounted in the lower compartment; and,

(i) said outlet means comprising a first opening through the rear wall of said upper compartment and a second opening through the rear wall of said lower compartment.

2. A marine propulsion unit for propelling a boat as defined in claim 1, wherein:

(a) said first and second openings of said outlet means are offset vertically and horizontally from each other.

3. A marine propulsion unit for propelling a boat as defined in claim 2, wherein:

(a) said means for operatively connecting the propellers to a power means includes a pair of substantially vertically disposed telescopically related drive shafts.

4. A marine propulsion unit for propelling a boat as defined in claim 3, wherein:

(a) said means for operatively connecting the propellers to a power means includes,

(1) gear means connected to said drive shafts;

(2) a power driven shaft; and,

(3) clutch means for connecting the power driven shaft to said gear means.

5. A marine propulsion unit for propelling a boat as defined in claim 4, wherein:

(a) said propeller housing is carried on a tubular shaft that is rotatably mounted on said support housing.

6. A marine propulsion unit for propelling a boat as defined in claim 5, wherein:

(a) said propeller housing is adjustably carried on said tubular shaft.

7. A marine propulsion unit for propelling a boat as defined in claim 6, wherein:

(a) said means for rotating the propeller housing is attached to said tubular shaft.

References Cited UNITED STATES PATENTS 1,441,519 1/1923 Motte 60-221 1,821,450 9/ 1931 Stelzer 170--135.28 2,112,948 4/ 1938 Anderson 60221 2,531,032 11/1950 Desmoulins 170-135.28 XR 2,702,516 2/1955 Tinker 60221 XR 2,743,698 5/1956 Leonard et :al 16 3,098,464 7/1963 Holland 60-221 XR CARLTON R. CROYLE, Primary Examiner. 

